Lubricating compositions and polymeric additives therefor



United States Patent v' of Delaware No Drawing. Filed Apr. 9, 1962, Ser. No. 185,833 Claims priority, application Netherlands, May 2, 1961, 264,248, 264,249

18 Claims. (Ci. 25249.9)

This invention relates to improved lubricating oil composition and to multifunctional oil-soluble additives therefor having improved detergent and wear-inhibiting properties and the like.

Combustion engines, such as gasoline engines and diesel engines, are more, or less subject to wear of cylinders, pistons and piston rings. In automobile engines, in particular, it is a known phenomenon that considerably increased wear occurs when the cylinder temperature remains relatively low, as is the case when driving short distances. According to the general view this is due to moisture condensing on the cool cylinder walls in the presence of acids, such as sulfuric acid from sulfurous fuel, hydrochloric acids from lead scavengers, and organic acids from incompletely burnt gasoline. The corrosion caused by these acids, also termed cold corrosion, is responsible for much of the piston and cylinder wear in automobiles.

In order to inhibit wear in combustion engines, it has already been proposed to incorporate in the lubricating oil certain additives capable of rendering the said acids harmless by neutralizing them. Examples are oil-soluble neutral or basic organic metal compounds, such as calcium, barium or zinc salts of petroleum sulfonic acids, of alkylated hydroxy benzoic acids, of dialkyl dithiophosphoric acid and others. In many cases it has been possible to obtain good results by incorporating such organic metal salts in the lubricating oil. The use of metal salts, however, is attended by drawbacks. One disadvantage, for example, is the fact that the metal salts formed by neutralization of the acids resulting from the combustion are generally insoluble in oil. This may lead to disturbances, particularly as a result of the formation of deposits in the combustion space which may subsequently cause precombustion.

It has now been discovered that an excellent multi functional lubricant is provided by incorporating into a base lubricant a small amount of an oil-soluble polymeric compound having essentially a hydrocarbon backbone chain and attached thereto in uniform or random fashion two essential units or groups (A) and (B) of which unit (A) provides the antiwear, antisludge and detergent properties while (B) provides the oleophilic and supplementary properties such as pour point, viscosity index improving properties to the polymeric compound. The (A) portion is polar in character and is selected from the groups consisting of (A which is represented by v n-N n"'1 (o R and (A which is represented by T T no" IIT-R-OIIOR where R is a hydrocarbyl radical, e.g., alkyl, aryl, alkaryl, aralkyl and cycloalkyl radicals which radicals may contain substituents such as hydroxyl groups. R is a radical of from 1 to 18, preferably 1 to carbon atoms. R" is a hydrocarbylene radical, e.g. alkylene, arylene, al-

3,22,608 Patented Aug. 24, 1965 karylene, aralkylene and cycloalkylene radicals 'of from 1 to 18, preferably 10 carbon atoms and R is a hydrocarbyl radical, e.g. alkyl, aryl, alkaryl, aralkyl and cycloalkyl radicals of from 1 to 18, preferably 1 to 10 carbon atoms. The oleophilic group (B) may be a hydrocarbyl radical of 8 to carbon atoms attached directly to the backbone chain, e.g., C1248 straight or branch-chain alkyl radical or indirectly attached to the backbone chain throughra polar group such as -co:a, -o-o-n or --OR, where R is defined. Polymers of this invention contain a plurality of groups or units (A) and (B). The molecular weight of the polymer ranges from about 10,000 to over 1,000,000, preferably from about 25,000 to about 500,000. The polymers of this invention may be prepared by copolymerizing a polymerizable compound containing at least one carbonyl group C=O) with a polymerizable compound containing a hydrocarbyl group of at least 8 carbon atoms and treating the resultant copolymer with a primary amine so as to convert the carbonyl groups to aldimine or ketimine groups or with a secondary amine containing a hydroxyl group so as to convert the carbonyl groups to alpha-hydroxy amine groups; followed by treatment with an organic phosphite'so as to finally form groups represented by (A and (A depending upon the amine used in the reaction. Thus, with primary hydrocarbyl amines such as alkylamine or substituted alkylamine, e.g. ethylamine or ethanolamine, followed by phosphite treatment, group (A radicals form whereas with alkylalkanolamines or dialkanolamines such as ethylethanolamine or diethanolamine followed by phosphite treatment group (A radicals form in the polymers of this invention.

The intermediate polymeric product (prior to aminephosphite treatment) from which the copolymers of this invention are derived can be obtained by copolymerization of a monomer containing a carbonyl group with a monomer containing an oleophilic group having at least 8 carbon atoms, or a copolymer obtained indirectly from these monomers, for example by reducing ester groups to aldehyde groups of a polymer or copolymer containing ester groups, or for example by oxidation of secondary alcohol groups present in a polymer or copolymer to ketone groups. Also copolymers containing acetal' groups and the oleophilic hydrocarbyl groups may be converted into copolymers containing carbonyl groups by treatment with mineral acid.

Examples of monomers of which the copolymers containing aldehyde groups may be composed are unsaturated aliphatic aldehydes. Preference is given to copolymers composed of acrolein or methacrolein and one or more monomers containing the oleophilic groups, or copolymers composed of a beta-formalacrylic' acid ester, maleic di-aldehyde or fumaric di-aldehyde, and one -or more monomers containing the oleophilic groups.

Copolymers containing ketone groups are also suitable copolymers which may be converted according to the invention into copolymers containing the polar groups (A) as described. Examples of suitable monomers of which copolymers containing ketone groups may be composed are unsaturated aliphatic ketones such as methyl isopropenyl ketone. I The monomers containing the oleophilic hydrocarbyl groups which may be used for the production of oilsoluble copolymers which contain carbonyl groups and are suitable for being converted into copolymers containing (A and/or (A groups are mono-olefins having a branched or straight carbon chain, in particular alpha-olefins having at least 10 carbon atoms, or esters of unsaturated organic monoand dicarboxylic acids and saturated alcohols, or esters of saturated organic carboxylic acids and unsaturated alcohol-s, which esters contain a saturated branched or straight carbon chain having at least 8 carbon atoms, or unsaturated aliphatic ethers having a saturated branched or unbranched carbon chain containing at least 8 carbon atoms. If desired, mixtures of these monomers may be used, for example a mixture of stearyl methacrylate and lauryl methacrylate. Of the esters of unsaturated monoand dicarboxylic acids and saturated alcohols esters of methacrylic acid are preferred, in particular methacrylic acid esters of which the ester group contains 12 to 18 carbon atoms. The esters of maleic acid and fumaric acid of which at least one of the ester groups contains at least 8 carbon atoms are also suitable for use. 7

Of the unsaturated aliphatic ethers preference is given to vinyl-alkyl ethers in which the alkyl group contains 12 to 18 carbon atoms.

The primary amines used to form the 'aldimine or ketimine groups are alkyl, aryl, aralkyl, alkaryl or cycloalkylamines which amines may contain substituents to the carbon atoms of their hydrocarbyl radicals, e.g., OH-groups, or polyamines. Examples of these amines are C alkylamines, such as ethyl, propyl, butyl, octyl, dodecyl, octadecyl amines, ethanolamine, propanolamine, phenylarnine, naphthylamine, benzylamine, toluidine, cyclohexylamine, ethylene diamine, propylene diamine, tetraethylene pentamine and mixtures thereof.

The secondary amines used to form the alpha-hydroxyamine groups are secondary amines containing at least one hydroxyl group attached to a carbon atom of the ,hydrocarbyl radicals of the amine. Examples of these secondary amines are methylmethanolamine, ethylethanolamine, diethanolamine, propylpropanolamine, di- .propanol'amine, etc.

The organic phosphites include dialkyl phosphites or dialkenyl phosphites, the alkyl or alkenyl radicals having from 1 to 18 carbon atoms such as dimethyl-, diethyl-, dipropyl-, dibutyL, dioctyl-, dilauryl-, distearyl-, dioleyl phosphites and their thio derivatives such as dimethyl .dithiophosphite, diethyl dithiophosphite and the like. Other phosphites may be used such as diphenyl phosphite, methyl phenyl phosphite, ethyl phenyl phosphite and the like.

The preparation of a copolymer according to the method invented, from a copolymer having a carbonyl group, for instance a copolymer of acrolein or methacrolein and an ester of an unsaturated acid such as methacrylic acid, and an alcohol having at least 8 carbon atoms, such as lauryl alcohol or stearyl alcohol, by reaction with an amine and a phosphite, is preferably performed at a temperature between 20 and 120 C., preferably in a solvent, especially in an aromatic hydrocarbon such as benzene, toluene and xylene. The water formed in the reaction between carbonyl group and primary amine when a primary amine is used, is preferably removed during the reaction by azeotropic distillation, the azeotrope being distilled off and, if desired, the solvent being replenished in the reaction mixture according as it distills over into the azeotrope.

The following examples illustrate the preparation of polymers of the present invention.

EXAMPLE I 100 parts by weight copolymer of methacrolein and stearyl methacrylate, in which copolymer the monomer ratio was 0.8 methacrolein unit to 1 stearyl methacrylate unit, were'dissolved in 270 parts by weight benzene. After addition of 24 parts by weight ethylamine, the mixture was stirred in a closed vessel for 3 days at a temperature of 20 C. Then the remainder of the amine was removed by evaporation at a temperature of 60 C., whereupon 44 parts by weight dimethyl phosphite were added. The mixture was boiled under reflux for 24 hours with stirring. Next, it was poured out into 1500 parts by weight methanol. The product which separated off was taken up in parts by weight benzene, whereupon the product was isolated by freeze drying. The yield was parts by weight product having a nitrogen content of 1.07% wt. and a phosphorus content of 1.39% wt.

EXAMPLE II parts by weight copolymer of acrolein and stearyl methacrylate, in which copolymer the monomer ratio was 1.1 acrolein unit to 1 stearyl methacrylate unit, were dissolved in 100 parts by weight benzene. After addition of 24.4 parts by weight monoethanolamine, the mixture was boiled under reflux for 18 hours, the water produced being removed by azeotropic distillation. Then 44 parts by weight dimethyl phosphite were added and the mixture was heated at 65 C. for 2.5 hours. The reaction mixture was poured out into 1000 parts by weight methanol, the product which separated off was taken up in 100 parts by weight benzene and the resultant solution poured out in 1000 parts by weight methanol. The product which separated off was taken up in 50 parts by weight benzene and then isolated by freeze drying. The yield was 152 parts by weight product with a nitrogen content of 1.65% wt. and a phosphorus content of 0.98% wt.

EXAMPLE III 188 parts by weight copolymer of acrolein and stearyl methacrylate, in which copolymer the monomer ratio was 0.8 acrolein unit to 1 stearyl methacrylate unit, were dissolved in 412 parts by weight benzene. The resultant solution was, after addition of 61 parts by weight monoethanolamine, boiled under reflux for 24 hours, the water produced being removed by azeotropic distillation. The reaction mixture was poured out into 3200 parts by weight methanol. The product which spearated off was washed with methanol. Finally, freeze drying yielded parts by weight product with a nitrogen content of 2.32% wt. This corresponds with a conversion of 86.3%, while from the amount of Water distilled off (9.7 parts by weight) a conversion of 87.0% is calculated.

179 parts by weight of this product containing 2.32% wt. nitrogen were dissolved in 450 parts by weight benzene. The solution was heated at 80 C. and 110 parts by weight dimethyl phosphite were added. As a result, the temperature rose by 4 C. After boiling under reflux for 18 hours with stirring, the reaction mixture was poured out into 3200 parts by weight acetone. After decanting of the solution so obtained, the precipitate was washed with acetone by stirring these two together and decanting again. Thereupon the product was stripped of solvents by freeze drying. The yield was 190 parts by weight, with a nitrogen content of 1.94% wt. and a phosphorus content of 3.80% wt. Calculated on phosphorus content, the conversion was 87.4%.

EXAMPLE IV The starting material was a copolymer of methacrolein and stearyl methacrylate, containing 1.3 methacrolein units per stearyl methacrylate unit.

134.5 parts by weight of this copolymer were dissolved in 459.0 parts by weight benzene. After addition of 36.6 parts by Weight monoethanolamine, the mixture was boiled under reflux'for 23 hours with stirring. The water produced was distilled off azeotropically. Then a further 12.2 parts by weight monoethanolamine were added and boiling under reflux was continued for another 7 hours with stirring, the reaction water formed being removed azeotropically. The reaction product was poured out into 2000 parts by weight methanol, the product which separated off was dissolved in 250 parts by weight benzene and the solution poured out into 2000 parts by weight methanol. The product which separated off was washed with methanol and then isolated by freeze drying. The

yield amounted to 119 parts by weight product with a nitrogen content of 2.2% wt.

119 parts by weight of this product containing 2.2% N weredissolved in 481 parts by weight benzene. After addition of 88 parts by weight dimethyl phosphite, the mixture was boiled under reflux for 24 hours withstirring, and then poured out into 2000 parts by weight methanol. The reaction product which separated off was Washed with methanol, taken up in 200 parts by Weight benzene and recovered from the resultant solution by freeze drying. The yield amounted to 108 parts by weight product having a nitrogen content of 1.99% wt. and a phosphorus content of 3.80% wt.

. EXAMPLE V The starting material was a copolymer of acrolein and stearyl methacrylate, containing 1 stearyl methacrylate unit per acrolein unit.

1443 parts by Weight of this copolymer Were dissolved in 2257 parts by weight benzene. After addition of 244 parts by weight monoethanolamine, the mixture was boiled under reflux for 24 hours with stirring. Upon addition of 440 parts by weight dimethyl phosphite, heating to boiling point was continued for another 7.5 hours with stirring. Thereupon a further 200 parts by weight dimethyl phosphite were added and the mixture was boiled under reflux for another 24 hours withstirring. After pouring out into 15,000 parts. by weight methanol, the productfwhich separated off was washed with methanol and then recovered by freeze drying. The yield amounted to 1151 parts by weight product with, a nitrogen content of 1.50% Wt. and a phosphorus content of 2.31%. Wt.

EXAMPLE VI 7 amounted to 97 parts by weight of product with a nitrogen content of 0.46% wt. and a phosphorus content of 0.76% wt.

EXAMPLE 1X product with a nitrogen contentof 1.33% Wt. and a'phosphorus'content of 0.71% wt.

EXAMPLE v11 100 parts. by weight of a copolymer of methacrolein and stearyl methacrylate, containing 0.8 methacrolein unit per stearyl methacrylate unit, were dissolved in 270 parts by Weight benzene. After addition of 58 parts by weight aniline, the mixture was boiled under reflux for 24 hours with stirring. The water thereby formed was removed by azeotropic distillation. The reaction mixture was poured out into 1000 parts by Weight methanol, andthe product which separated off taken up in 250 parts by weight benzene. After addition of 44 parts by weight dimethyl phosphite, the mixture was boiled under reflux for 24 hours with stirring. Then it was poured out into 1000 parts by weight methanoL'the 'reaction product which separated off was taken up in 100 parts by weight benzene and isolated by freeze drying. The yield amounted to 120 parts by weight producthaving a nitrogen content of 0.79% wt. and a phosphorus content of 1.12% Wt. i

1 EXAMPLE VIII As starting material was takena copolymer of acrolein and stearyl methacrylate which per acrolein unit contained 1 stearyl methacrylate unit. 103.7 parts by-weight of this copolymer were dissolved in 216 parts by weight of benzene. To this solution 42 parts by weight of diethanolamine and 55.2 parts by weight of diethyl phosphite were added, after which the mixture was boiled 130 parts by weight of a copolymer of acrolein and stearyl methacrylate which to every 1.1 acrolein units contained 1 stearyl methacrylate unit, were dissolved in 65 parts by weight of benzene. To the solution 42 parts by Weight of diethanolamine were added, after which the mixture was heated at 70 C. for 30 minutes, while being stirred. Next, while stirring was continued, 44 parts by Weight of dimethyl phosphite were added and heating at 70 C. was continued for one hour. Subsequently, the reaction mixture, after cooling down, was poured into 1000 parts by weight of methanol. separated Was taken up in 50 parts by weight of benzene, after which the solution obtained was poured into 1000 parts by weight of methanol. The product which separated was freed from solvents by freeze drying. The yield amounted to 141 parts by weight of product with a nitrogen content of 0.44% wt. and a phosphorus content of 0.53% wt.

EXAMPLE X and stearyl methacrylate which per acrolein unit contained 1 stearyl methacrylate unit. 1443 parts by weight of this copolymer were dissolved in 2257 parts by weight of benzene. After addition of 420 parts by'weight of diethanolamine the mixture obtained was heated under reflux for 42 hours. Next, 440 parts by weight of dimethyl phosphite were added and after boiling under reflux for 12 hours the reaction mixture was cooled and ,poured into 15,000 parts by weight of methanol. The separating product was taken up in 1000 parts by weight of benzene and isolated from the solution obtained by freeze drying. The yield amounted to 1436 parts by Weight of product with a nitrogen content of 0.81% wt. and a phosphorus content of 0.68% wt.

EXAMPLE x1 188 parts by weight of an acrolein stearyl acryl-ate copolymer which to each 0.8 acrolein unit contained 1 stearyl methacrylate unit, were dissolved in 412 parts by weight of benzene. After addition of parts by Weight of diethanolamine the solution was boiled under reflux, for. 18 hours while being stirred. To the reaction mixture parts by weight of dimethyl phosphite were added, after which boiling under reflux was continued for 3 hours while stirring was applied The reaction mixture obtained .was cooled and poured into 3200 parts by weight of methanol. The precipitated product was dissolved in 200 parts by weight ofbenzene and the solution obtained was poured into 3200 parts by weight of methanol. The methanol layer was decanted from the precipitated product. The product was washed with methanol and isolated by freeze drying. The yield amounted to 190 parts by weight. The prodnot contained 1.55% wt. of nitrogen and 1.25% Wt. of

phosphorus. V

The copolymers according to the invention make suitable additives to avariety of lubricants. In the 'first place mineral lubricating oils of varying viscosity may be mentioned, e.g., mineral oils having a viscosity at 100 F. of 100 to 250 SUS. A typical mineral lubricatin oil (X) of this type is an extracted Venezuelan parafzfiniclubricating oil having a viscosity of 114 cs. at 100 The product which F. and a California mineral lubricating oil (Y) may have the following properties:

Gr. API, 60/ 60 F 32 Flash, F. 370 Viscosity index (Dean and Davis) 93 Viscosity, SUS at100 F 103 Also, synthetic lubricating oils can be improved by such additives, and so can lubricating oils containing fatty oils. Moreover, the products claimed can be incorporated in lubricating greases.

The copolymeric compounds claimed in the invention are also eligible for use as additives in liquid fuels, such as gasoline, kerosine, gas oil .and residual fuels.

The products claimed can be added as such to the lubricant. An advantageous procedure is tostrip the product, after the preparation, only partly of the solvent, for example by distillation under reduced pressure or by steam distillation; next, a small amount of a lubricating oil is added and finally the remainder of the solvents is distilled off with steam, preferably under reduced pressure. The concentrate so obtained 'can then be diluted with a lubricant and/or processed into :a lubrieating grease.

The amount of the products claimed in the invention which is added to lubricants can vary within wide limits. In general the desired improvement is reached when the amount of from 0.1%to or 0.2% to 5% or more, in particular between 1 and 3%, of the finished lubricant. In special cases, however, still higher ercentages than these can be applied, for example in diesel engines running on fuel with .a high sulfur content.

When desired, additional improvements with respect to oxidation stability and scufiing inhibition can be imparted to the oil compositions containing the copolymers of this invention by incorporating small amounts (0.01-2%, preferably 0.11%) of phenolic antioxidants such as alkylphenol, e.g. 2,6-ditert.butyl-4-methyl phenol or p,pmethylene bisphenol-s such as 4,4'-methyl'ene (2,6-ditert. butyl phenol) of arylamines such as phenylalphanaphthylamine and mixtures thereof. Anti-'scuffing agents include organic phosphites, phosphates, pho'sphonates and their thio-derivatives, uch as C alkyl phosphites, or phosph'onates, e.g. diand tributyl, otcyl lauryl, stearyl, cyclohexyl, benzyl, cresyl, phenyl, phosphites or phosphates, as well as their thio-derivatives, P S -terpene reaction products, e.g. P S -pine oil reaction prodnet and alkali metal salts thereof such as potassium salt of a P S -terpene reaction product, phosphonates such -as dibutyl rnethanephosphonate, dibutyl trichlorornethanepho-sphonate, dibutyl m-onochloromethanephosphonate, dibutyl chlorobenzenephosphonate, and the like. The full esters of pentavalent phosphorus acids such as triphenyl, tricresyl, tristearyl ortho phosphonates' or potassium salt of P S -terpene reaction product are preferred.

The following non-ash compositions are representative of this invention.

Composition A:

Example I copolymer 2% wt.

Mineral lubricating oil (X) Balance. Composition B:

Example II copolymer 2% wt.

Mineral lubricating oil (X) Balance. Composition C:

Example III copolymer 2% wt.

Mineral lubricating oil (X) Balance. Composition D:

Example IV copolymer 2% wt.

Mineral lubricating oil (X) Balance. Composition E: v

Example V copolymer 2% Wt.

Mineral lubricating oil (X) Balance.

8 Composition -F:

Example I copolymer 2% wt. 4,4'-methylene bis(2,6-ditert.butyl I phenol) 0.75% Wt. Mineral lubricating oil (X) Balance. Composition G:

Example I copolymer 5% Wt. 4,4-methylene bis(2,6-ditert.buty1 phenol) 0.5% wt. Tricresyl phosphate 0.8% wt. Mineral lubricating oil (X) Balance. Composition H:

Example I copolymer 5% wt. 4,4'-methylene bis(2,6-ditert.butyl phenol) 0.5% wt. P S -terpene reaction product 1% wt. Mineral lubricating oil (X) Balance. Composition I:

Example I copolymer 2% wt. Fuel oil (No. 2)v Balance. Composition J: v Example VIII copolymer 2% wt.

Mineral lubricating oil (X) Balance. Composition K:

Example 1X copolymer 2% wt. Mineral lubricating oil (X) Balance. Composition L:

7 'Example X copolymer 2% wt. Mineral lubricating oil (X) Balance. Composition M: I

Example XI copolymer 2% wt. Mineral lubricating oil (X) Balance. Composition N:

Example VIII copolymer 2% wt. 4,4'-rnethylene bis(2,6-ditert.buty1 phenol) 0.75% wt. Mineral lubricating oil (X) Balance. Composition 0:

Example VIII copolymer 5% wt. 4,4'-Inethylene bis(2,6-ditert.butyl phenol) 0.5% wt. Tricresyl phosphate 0.8% wt. Mineral lubricating oil (X) Balance. Composition I:

Example VIII copolymer 5% wt. 4,4'-rnethylene bis(2,6-ditert.butyl phenol) 0.5% wt. P S -terpene reaction product 1% wt. Mineral lubricating oil (X) Balance. Composition Q:

Example VIII copolymer 2% wt. Fuel oil (No. 2) Balance.

Properties Solutions of the products claimed in the invention were examined for anti-wear properties, detergency and anti-sludge properties.

Anti-wear properties Bore mm 83.85 Stroke mm 114.3 Swept volume cm. 628

The duration of each test was 45 hours; the fuel was a gasoline with a sulfur content of 0.05% wt., contain- 9 ing 1.2 ml. TEL per USG. The temperature of the cylinder cooling water was approx. 40 C.

TEST RESULTS IN FOUR-BALL TOP. I CONCENTRATION OF ADDITIVE 2% WT.

CFR WEAR TEST Percent reduction in piston ring wear vis-a-vis the base oil Compositi-on'A 69 Composition B 77 Composition C 74 Composition C (1% of Example V copolymer) 69 Composition L 57 Composition M Detergency The cleansing action of the additives claimed in the invention was determined in engine tests, carried out in a Gardner diesel engine and in a Caterpillar diesel engine. The concentration of the additive in the extracted Venezuelan paraffinic lubricating oil was 2% wt.

Gardner enginer- Wa-ter cooled single-cylinder fourstroke engine. The duration of each test was 17 hours; the fuel was a gas oil with a sulfur contentof 0.9% Wt. The cooling water temperature was approx; 80 C. The engine had an output of 1 1 HP. anda bore of 108 mm., a stroke of 152.4 mm, and a swept volume of 1.4 liters.

Caterpillar engine.Water-cooled single-cylinder fours-troke engine. The duration of each test was 48 hours, and the fuel a gas oil with a sulfur content of 0.9 wt. The cooling water temperature was approx. 80 C. The engine had an output of 18 I-LP. and .a bore of 146 mm, a stroke of 203.2 mm., andswept volume of 3.4 liters.

PISTON FOULING TESTS IN GARDNER AND CATERPILLAR DIESEL ENGINES Rating (oi Piston Fouling 10=c1ean) Gardner Caterpillar Diesel Diesel Base oil without additive 4. 4 4. 7 Composition A 6. 4 Composition B 7. 8 Composition 7.3 8.0

Anti-sludge properties The duration of each test was 28' Results 7 Sludge rating (l10=clean) Base oil without additive 4.4

- Composition A 7.6 Composition B 7.1 Composition I a 7.4 Composition K 7.3

- Composition M 6.1

Lubricating compositions of this invention are particularly applicable tor high temperature, high speed use as in aviation engines, automotive engines, truck engines as well as industrial equipment.

I claim as my invention: 1. A mineral lubricating oil composition comprising a major amount of mineral lubricating oil and from 0.1%

to 10% of an oil-soluble reaction product obtained by reacting between 20 C. and C. in the presence of an aromatic hydrocarbon solvent, a copolymer of an unsaturated aldehyde selected from the group consisting of acrolein and methacrolein and a C1248 alkyl methacrylate, in which the monomer ratio is from about 0.8:1 to about 1.3:1, respectively, with an amine selected from the group consistingof an alkylamine and an alkanolamine, to form aplurality of aldimine groups in the copolymer, followed by treatment with an alkyl phosp-hite, the final product having a nitrogen content of from about 0.44%.to about 1.99% nitrogen and a phosphorus content .of from about 0.53% to about 3.80% and a molecular weight of from 10,000 to 1,000,000.

2. The composition of claim 1 wherein the amine is an alkyl-arnine and the alkyl phosphite is a dialkyl pho=sphite. i

3. The composition of claim 1 wherein the amine is an alkanolamine and the alkyl phosphite is a dialkyl phosphite.

4. A mineral lubricating oil composition comprising a major amount of mineral lubricating oil and from 0.1% to 10% of an oil-soluble reaction'product obtained by reacting between 20 C. and 120 C. in the presence of an aromatic hydrocarbon solvent a copolymer of an unsaturated aldehyde selected from the group consisting of acrolein and'methacrol'ein and a C alkyl methacrylate, in which the monomer ratio is :from about 0.811 to about 13:1, respectively, with an alkanolamine to form a plurality of alpha-hydroxyamine groups in the co 'nolymer, followed by treatment with an 'alkyl phosphite, thefinal product having a n-itrogencontent of from about 0.44% to about 1 .99% nitrogen and a phosphorus content of from about 0.53% to about 3.80% and a molecular weight of from 10,000 to 1,000,000.

5. The composition of claim 4 wherein the amine is by reacting at "about 20 C. in benzene a copolymer of methacrolein and stearyl methacrylate in which the monomer ratio is about 0.8 to'l, respectively, with ethylamine followed by reaction with dirnethylphosphite at about 60 C. to form a final product having a nitrogen content of about 1.07% and a phosphorus content of about 1.39% and having a molecular weight of from 8. A mineral lubricating oil composition comprising a major amount of mineral lubricating oil and from 0.1% to 10% of an oil-soluble reaction product obtained by reacting between 20 C. and 120 C. in the presence of benzene solvent a copolymer of acrolein and stearyl methacrylate in which the monomer ratiois about 1: 1 respectively, with monoethanolamine, followed by treatment with dimethyl phosphite, the final product having a nitrogen content of from about 1.33% to about 1.99% and a phosphorus content of from about 0.71% to about 3.80% and a molecular weight of from 10,000 to 1,000,- 000.

9. A mineral lubricating oil composition comprising a major amount of mineral lubricating oil and from 0.1% to of an oil-soluble reaction product obtained by reacting between 20 C. and 120 C. in the presence of benzene solvent a copolymer of acrolein and stearyl methacrylate in which the monomer ratio is about 1:1 respectively, with diethanolamine, followed by treatment with dimethyl phosphite, the final product having 2. nitrogen content of from about 0.44% to about 1.55% and a phosphorus content of from about 0.53% to about 1.25% and a molecular weight of from 10,000 to 1,000,- 000.

10. As a new compound, an oil-soluble reaction product obtained by reacting between 20 C. and 120 C. in the presence of an aromatic hydrocarbon solvent a copolymer of an unsaturated aldehyde selected from the group consisting of acrolein and methacrolein and a C alkyd met-haorylate, in which the monomer ratio is from about 0.8:1 to about 1.3:1, respectively, with an amine selected from the group consisting of an alkylamine and an alkanolamine to form a plurality of aldimine groups in the copolymer, followed by treatment with an 'alfyl phosphite, the final product having a nitrogen content of from about 0.44% to about 1.99% nitrogen and a phosphorus content of from 0.53% to 3.80% and a molecular weight of from 10,000 to 1,000,000.

1-1. As a new compound a compound of claim 10 wherein the amine is an alkylamine and the alkyl phosphite is a dialkyl phosphite.

12. As a new compound a compound of claim 10 wherein the amine is an alkanolamine and the alkyl phosphite is a dialkyl phosphite.

13. As a new compound, an oil-soluble reaction product obtained by reacting between 20 C. and 120 C. in the presence of an aromatic hydrocarbon solvent a copolymer of an unsaturated aldehyde selected from the group consisting of acrolein and methacrolein and a C1248 alkyl met-hacrylate, the units of the unsaturated aldehyde and C arlkyl methaorylate ranging from about 0.8:1 to 1.3:1, respectively, with an alkanolamine to form a plurality of alpha-hydroxyamine groups in the copolymer, followed by treatment with an alkyl phosphite, the final product having a nitrogen content of from about 0.44% to about 1.99% nitrogen and a phosphorus content of from about 0.53% to about 3.80% and a molecular weight of from 10,000 to 1,000,000.

14. As a new compound a compound of claim 13 wherein the amine is an alkanolamine and the alkyl phosphite is dialkyl phosphite.

15. As a new compound a compound of claim 13 wherein the amine is a dialkanolamine and the alkyl phosphite is a dialkyl phosphite.

16. As a new compound, an oil-soluble reaction product obtained by reacting at about 20 C. in benzene a copolymer of methacrolein and stearyl methacrylate in which the monomer ratio of methacrolein to stearyl methacrylate is 0.8 to 1, respectively, with ethylamine followed by reaction with dimethyl phosphite at about C. to form a final product having a nitrogen content of about 1.07% and a phosphorus content of about 1.39% and having a molecular weight of from 10,000 to 1,000,000.

17. As a new compound, an oil-soluble reaction product obtained by reacting between 20 C. and C. in the presence of benzene solvent a copolymer of acrolein and stearyl methacrylate in which the monomer ratio is about 1:1 respectively, with monoethanolamine, followed by treatment with dimethyl phosphite, the final product having a nitrogen content of from about 1.33% to about 1.99% and a phosphorus content of from about 0.71% to about 3.80% and a molecular weight of from 10,000 to 1,000,000.

'18. As a new compound, an oil-soluble reaction product obtained by reacting between 20 C. and 120 C. in the presence of benzene solvent a copolymer of acrolein and stearyl methacrylate in which the monomer ratio is about 1:1 respectively, with d iethanolamine, followed by treatment with dimethyl phospbite, the final product having a nitrogen content of from about 0.44% to about 1.55% and a phosphorus content of from about 0.53% to about 1.25% and a molecular weight of from 10,000 to 1,000,000.

References Cited by the Examiner UNITED STATES PATENTS 2,800,450 7/57 Bondi et al 252-46.6 X 2,956,952 10/60 Fitzgerald et al. 252-49.9 3,022,261 2/62 Fields et a1 252-498 X 3,030,347 4/62 OBrien et al. 26086.1

DANIEL E. WYMAN, Primary Examiner. 

1. A MINERAL LUBRICATNG OIL COMPOSITION COMPRISING A MAJOR AMOUNT OF MINERAL LUBRICATING OIL AND FROM 0.1% TO 10% OF AN OIL-SOLUBLE REACTION PRODUCT OBTAINED BY REACTING BETWEEN 20*C. AND 120*C. IN THE PRESENCE OF AN AROMATIC HYDROCARBON SOLVENT, A COPOLYMER OF AN UNSATURATED ALDEHYDE SELECTED FROM THE GROUP CONSISTING OF ACROLEIN AND METHACROLEIN AN A C12-18 ALKYL METHACRYLATE, IN WHICH THE MONOMER RATIO IS FROM ABOUT 0.8:1 TO ABOUT 1.3:1, RESPECTIVELY, WITH AN AMINE SELECTED FROM THE GROUP CONSISTING OF AN ALKYLAMINE AND AN ALKANOLAMINE, TO FORM A PLURALITY OF ALDIMINE GROUPS IN THE COPOLYMER, FOLLOWED BY TREATMENT WITH AN ALKYL PHOSPHITE, THE FINAL PRODUCT HAVING A NITROGEN CONTENT OF FROM ABOUT 0.44% TO ABOUT 1.99% NITROGEN AND A PHOSPH/ RUS CONTENT OF FROM ABOUT 0.50% TO ABOUT 3.80% AND A MOLECULAR WEIGHT OF FROM 10,000 TO 1,000,000. 